WASHINGTON (AP) — Republican presidential hopeful Mitt Romney on Saturday denounced “poisonous language” against faiths as he grappled with a flare-up over religion sparked by a prominent supporter of Texas Gov. Rick Perry, his rival. Perry steered well clear of that simmering issue and pushed another hot button instead: Social Security.

Romney, in remarks to the Values Voters Summit, a gathering of cultural conservatives in Washington, did not directly confront the words of a prominent Perry supporter who called Romney’s Mormon faith a “cult.” Indeed, Romney was criticizing another speaker at the meeting who is known for anti-Mormon and anti-Muslim rhetoric, and who followed him on stage.

But his cautionary words served as notice that attacks on faiths should, in his view, be off the table. He appealed to the social conservatives to support a presidential candidate who has the best record on the economy.

Until now, Romney’s Mormon faith and Perry’s evangelical Christianity were secondary to a GOP primary focused on who can best fix the country’s economy. Questions about his faith plagued Romney’s 2008 presidential run, but he had been able to keep them at bay so far this time.

That changed when a pastor who introduced Perry to cultural conservatives called Mormonism a “cult” and said Romney is “not a Christian,” forcing Perry to distance himself and Romney to respond. The back-and-forth suggests the primary race — with a field finally settled and just three months before voting begins — has moved into a more aggressive phase. And it illustrates that Perry’s very public religiosity and long history with evangelical Christian leaders won’t remain on the sidelines of the presidential race.

But Perry, campaigning Saturday in Iowa’s staunchly conservative northwest, barely touched on religion at all. In stops at Sioux City and Orange City, he never mentioned Mormonism, Romney by name, or even Christianity, for that matter.

Asked by Republican Steven Bernston what books have most influenced him, Perry mentioned only one: the work of conservative economist Friedrich Hayek. Bersnton, a corn and beans farmer from Paullina, later said he was surprised that Perry didn’t at least mention the Bible.

“I don’t think he’s a reader,” Bernston said in an interview, noting that Perry used the question to switch to previous statements about his opposition to government efforts to stimulate the economy.

Perry waded back into Social Security instead, a tricky issue for him after he roundly criticized the popular entitlement in his book and his Republicans rivals piled on against him. Responding to a question in Sioux City, he said “it makes sense” to increase the eligibility age for benefits and it may be time to reduce those benefits for the wealthy, a process known as means-testing.

In each of four Iowa campaign stops over two days, Perry took questions from voters, and none from reporters. None of the questioners mentioned Mormonism or asked overtly religious questions.

On Friday, Robert Jeffress, the lead pastor at First Baptist Church in Dallas, introduced Perry as “a committed follower of Christ.” Perry thanked him, and said Jeffress had “hit it out of the park.” Afterwards, Jeffress told reporters Romney was “not a Christian” and that Mormonism is a “cult.” Jeffress had repeatedly made similar comments during Romney’s 2008 campaign.

Mormonism sparks concern among evangelical Christians, a critical bloc of voters in the Republican primary. Many do not believe that Mormons are Christian because they also rely on the Book of Mormon as a holy text, which they view as deviating from the Jesus Christ who is portrayed in the Bible.

At an event in Iowa later Friday, Perry was asked if he believes Mormonism is a cult. “No,” Perry said.

On Saturday, Romney answered Jeffress’ charge: He praised former Reagan official Bill Bennett, who spoke ahead of Romney at the conference. “You did Rick Perry no good, sir, in what you had to say,” said Bennett, denouncing Jeffress for “bigotry” against Mormons.

“Speaking of hitting it out of the park, how about that Bill Bennett!” Romney said as soon as he took to the podium.

It was a subtle but unmistakable rebuttal. Romney also asked Jay Selukow, a conservative lawyer who publicly debated Jeffress over Romney’s religion in 2008, to introduce him. And Romney’s campaign had been in touch with Bennett ahead of the conference because they were concerned about a different speaker, American Family Association Bryan Fischer, Bennett told The Associated Press.

Bennett called for unity among conservatives as they choose a nominee for president in 2012.

Romney echoed that call in his remarks. “We should remember that decency and civility are values too. One of the speakers who will follow me today has crossed that line, I think,” Romney said, referring to Fischer, who has made anti-Mormon and anti-Muslim remarks in the past. “Poisonous language doesn’t advance our cause. It’s never softened a single heart nor changed a single mind.”

In the 2008 campaign, Romney endured criticism about his faith from rival Mike Huckabee, a Baptist minister.

So far, none of Romney’s rivals has directly attacked his faith — and Romney has dismissed the issue in interviews. “The great majority of Americans understand that this nation was founded on the principle religious tolerance and liberty so most people do not make their decision based on someone’s faith,” he said earlier this year.

But Perry’s sudden entry into the race — he announced his candidacy in August — forced the Romney campaign to go on offense. Perry raised $17 million in the first six weeks of his campaign and is building infrastructure to challenge Romney across the primary map, and particularly in Iowa and South Carolina, where evangelical voters are large and influential segments of the primary electorate.

And while Perry’s religion stayed out of race at first, the overt and political nature of his faith was bound to change that.

He has deep ties to evangelical Christian leaders, particularly in the South. In early August, Perry convened a prayer rally that drew more than 20,000 people to a football stadium in Houston. While his advisers insist his appearance was not political, Perry attended fundraising dinners for the event as part of his official schedule as governor, and he hit on political themes during his appearance there.